<!doctype html>
<html lang="zh-CN">
<head>
  <meta charset="utf-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
  <title>Bootstrap 101 Template</title>
  <!-- Bootstrap -->
  <link rel="stylesheet" href="./bootstrap-3.4.1-dist/css/bootstrap.min.css">
</head>
<body>
<!-- 
  按钮：<a>  <button>  <input>
  由三个类组成
  按钮的基础样式：btn 
  按钮颜色：btn-primary  btn-success ...
  按钮尺寸：btn-lg  btn-sm btn-xs ...
 -->

<div class="container">
  <button class="btn btn-default btn-lg">按钮1</button>
  <button class="btn btn-primary">按钮2</button>
  <button class="btn btn-success btn-sm">按钮3</button>
  <button class="btn btn-info btn-xs">按钮4</button>
  <button class="btn btn-warning" disabled>按钮5</button>
  <button class="btn btn-danger active">按钮6</button>
</div>
  
</body>
</html>